The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A111687 Comprimorial(n): the product of the first n primes and the first n composite numbers. 2
 8, 144, 5760, 362880, 39916800, 6227020800, 1482030950400, 422378820864000, 155435406077952000, 81137281972690944000, 50305114823068385280000, 39087074217524135362560000, 35256540944206770097029120000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Harvey P. Dale, Table of n, a(n) for n = 1..215 FORMULA a(n) = A002110(n)*A036691(n) for n>=1. - Rick L. Shepherd, Aug 20 2005 EXAMPLE a(1) = 2*4 = 8, a(2) = (2*3)*(4*6)=144. MATHEMATICA Module[{nn=50, prs, coms, len}, prs=Select[Range[nn], PrimeQ]; coms=Complement[ Range[4, nn], prs]; len=Min[Length[prs], Length[coms]]; Rest[FoldList[ Times, 1, Times@@@Thread[{Take[prs, len], Take[coms, len]}]]]] (* Harvey P. Dale, Jan 11 2014 *) CROSSREFS Cf. A002110 (primorials), A036691 (compositorials). Sequence in context: A341957 A024284 A024285 * A231851 A071305 A172150 Adjacent sequences: A111684 A111685 A111686 * A111688 A111689 A111690 KEYWORD nonn AUTHOR Amarnath Murthy, Aug 17 2005 EXTENSIONS Corrected and extended by Rick L. Shepherd, Aug 20 2005 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified May 29 20:11 EDT 2024. Contains 372952 sequences. (Running on oeis4.)